阅读说明：本技术 气体供应系统 (Gas supply system ) 是由 兼井直史 名仓见治 于 2019-05-24 设计创作，主要内容包括：本发明提供一种气体供应系统,其包括：贮存第一低温液化气体的第一罐；在第一罐内第一低温液化气体气化而发生的第一气体被流入,且配置有使第一气体升压的气体升压机构的第一路径；从第一罐取出第一低温液化气体,且配置有使第一低温液化气体升压的泵和使通过泵而升压的第一低温液化气体气化的气化机构的第二路径；以及使从第一路径中的气体升压机构的上游侧取出的第一气体的至少一部分液化并使其流入第二路径中的泵的上游侧,且配置有利用第二低温液化气体或第二气体冷却第一气体的冷却换热器的再液化路径。据此,能够向需求方供应升压为指定的压力的气体,并且能够提高气体供应效率。(the present invention provides a gas supply system, comprising: a first tank for storing a first cryogenic liquefied gas; a first path through which a first gas generated by vaporizing the first low-temperature liquefied gas flows in the first tank and in which a gas pressure-increasing means for increasing the pressure of the first gas is disposed; a second path through which the first low-temperature liquefied gas is taken out of the first tank, and in which a pump for increasing the pressure of the first low-temperature liquefied gas and a vaporizing mechanism for vaporizing the first low-temperature liquefied gas increased in pressure by the pump are disposed; and a reliquefaction path in which at least a part of the first gas extracted from the upstream side of the gas pressure-increasing means in the first path is liquefied and flows into the second path on the upstream side of the pump, and a cooling heat exchanger for cooling the first gas with the second low-temperature liquefied gas or the second gas is disposed. Accordingly, the gas boosted to the specified pressure can be supplied to the demand side, and the gas supply efficiency can be improved.)

1. A gas supply system for supplying a mixed gas in which a first gas vaporized from a first cryogenic liquefied gas and a second gas vaporized from a second cryogenic liquefied gas having a lower temperature than the first cryogenic liquefied gas are mixed to a demand side, the gas supply system comprising:

A first tank storing the first cryogenic liquefied gas;

A first path into which the first gas generated by vaporization of the first low-temperature liquefied gas flows in the first tank, and in which a gas pressure increasing means for increasing the pressure of the first gas is disposed;

A second path through which the first low-temperature liquefied gas is taken out from the first tank, and in which a pump for increasing the pressure of the first low-temperature liquefied gas and a vaporizing mechanism for vaporizing the first low-temperature liquefied gas increased in pressure by the pump are disposed; and

A reliquefaction path through which at least a part of the first gas extracted from the first path upstream of the gas pressure-increasing means is liquefied and flows into the second path upstream of the pump, and a cooling heat exchanger for cooling the first gas with the second low-temperature liquefied gas or the second gas is disposed.

2. The gas supply system according to claim 1,

a reliquefaction-gas pressure-increasing mechanism that increases the pressure of the first gas extracted from the first path is disposed in the reliquefaction path.

3. The gas supply system according to claim 1 or 2,

The cooling heat exchanger is configured to: the first gas is cooled with the second cryogenic liquefied gas and the second cryogenic liquefied gas is warmed with the first gas.

4. The gas supply system according to claim 1 or 2,

The reliquefaction path is configured to: the first gas is liquefied by heat exchange with the first cryogenic liquefied gas taken out of the first tank.

Technical Field

The present invention relates to a gas supply system.

Background

Conventionally, as disclosed in japanese patent laid-open publication No. 2015-187049 (hereinafter, abbreviated as patent document 1), a gas supply system is known that supplies a mixed gas in which a natural gas and a hydrogen gas are mixed to a predetermined demand side. The gas supply system disclosed in patent document 1 supplies a mixed gas in which a hydrogen gas generated by dehydrogenation of an organic hydride and a natural gas are mixed as a fuel to a combustor of a gas turbine power generation module. In this combustor, the mixed gas (gas including hydrogen gas and natural gas) is combusted by compressed air supplied separately, thereby generating high-temperature and high-pressure combustion gas. The combustion gas rotationally drives the gas turbine, and the rotational energy of the gas turbine is converted into electric energy in the generator.

In the gas supply system disclosed in patent document 1, it is sometimes necessary to increase the pressure of a gas such as a natural gas or a hydrogen gas to a predetermined pressure and supply the gas to a predetermined demand side. The present inventors have conceived of such a situation and focused on the problem of increasing the efficiency of the entire system by reducing the energy of the entire gas supply system required to obtain a gas whose pressure is raised to a predetermined pressure as much as possible.

Disclosure of Invention

An object of the present invention is to provide a gas supply system capable of supplying a gas whose pressure is raised to a specified pressure to a demand side and capable of improving gas supply efficiency.

A gas supply system according to the present invention is a gas supply system for supplying a mixed gas in which a first gas vaporized from a first low-temperature liquefied gas and a second gas vaporized from a second low-temperature liquefied gas having a lower temperature than the first low-temperature liquefied gas are mixed to a demand side, the gas supply system including: a first tank storing the first cryogenic liquefied gas; a first path into which the first gas generated by vaporization of the first low-temperature liquefied gas flows in the first tank, and in which a gas pressure increasing means for increasing the pressure of the first gas is disposed; a second path through which the first low-temperature liquefied gas is taken out from the first tank, and in which a pump for increasing the pressure of the first low-temperature liquefied gas and a vaporizing mechanism for vaporizing the first low-temperature liquefied gas increased in pressure by the pump are disposed; and a reliquefaction path through which at least a part of the first gas extracted from the first path upstream of the gas pressure-increasing means is liquefied and flows into the second path upstream of the pump, and a cooling heat exchanger for cooling the first gas with the second low-temperature liquefied gas or the second gas is disposed.

According to the present invention, it is possible to supply gas whose pressure is raised to a specified pressure to a demand side, and to improve gas supply efficiency.

Drawings

Fig. 1 is a diagram schematically showing the configuration of a gas supply system according to embodiment 1 of the present invention.

Fig. 2 is a diagram schematically showing the configuration of a gas supply system according to another embodiment of the present invention.

Detailed Description

Hereinafter, a gas supply system according to an embodiment of the present invention will be described in detail with reference to the drawings.

(embodiment mode 1)

First, a gas supply system according to embodiment 1 of the present invention will be described with reference to fig. 1. Fig. 1 schematically shows main components of a gas supply system 1 according to embodiment 1 of the present invention.

The Gas supply system 1 is a system for supplying a mixed Gas G3, in which a first Gas G1 vaporized by first cryogenic Liquefied Gas L1 and a second Gas G2 vaporized by second cryogenic Liquefied Gas L2 having a lower temperature than first cryogenic Liquefied Gas L1 are mixed, to the demand side 100, in the present embodiment, a case will be described where the first cryogenic Liquefied Gas L1 is Liquefied Natural Gas (LNG), the first Gas G1 is Natural Gas (NG), the second cryogenic Liquefied Gas L2 is Liquefied hydrogen (LH ₂), and the second Gas G2 is Liquefied Gas (H ₂) as an example of the present invention, and the types of the first cryogenic L1 and the second cryogenic L2, and the first Gas G1 and the second Gas G2 are not limited to these.

The gas supply system 1 supplies a mixed gas G3, which is a mixture of a first gas G1 (natural gas) and a second gas G2 (hydrogen gas), as fuel to a combustion chamber of the gas turbine power generator (demand side 100). The demand 100 to which the mixed gas G3 is supplied is not limited to the combustion chamber of the gas turbine power generator.

As shown in fig. 1, the gas supply system 1 mainly includes a first gas supply unit 1A for supplying a first gas G1 and a second gas supply unit 1B for supplying a second gas G2. The respective configurations of the first gas supply unit 1A and the second gas supply unit 1B will be described in detail below.

first, the structure of the first gas supply portion 1A that supplies the first gas G1 (natural gas) will be described. As shown in fig. 1, the first gas supply portion 1A mainly includes a first tank 21, a first path 23, a second path 26, and a reliquefaction path 28.

The first tank 21 is used to store a first cryogenic liquefied gas L1 (LNG). The first low temperature liquefied gas L1 is stored in the first tank 21 at a temperature of about-162 c. In the first tank 21, a part of the first low-temperature liquefied gas L1 is vaporized (evaporated) by heat or the like from the outside, and thereby the first gas G1 is generated as an evaporated gas.

The first path 23 is a path into which the first gas G1 (boil-off gas) generated in the first tank 21 flows. As shown in fig. 1, one end of the first path 23 is connected to the upper portion of the first tank 21, and a first gas pressure-increasing means 22 for increasing the pressure of the first gas G1 to a predetermined pressure is disposed. Accordingly, the first gas G1 generated in the first tank 21 can be flowed into the first path 23 from one end of the first path 23, and can be pressurized to a predetermined pressure by the first gas pressure-increasing means 22.

The first gas pressure-increasing means 22 is, for example, a reciprocating compressor (reciprocating compressor) having a plurality of compression chambers provided therein. The first gas G1 is sucked into the compression chamber from the suction port of the first gas pressure-increasing means 22 through the first path 23. Then, in each compression chamber, the first gas G1 sucked into the cylinder is pressurized by the reciprocating motion of the piston, and the pressurized first gas G1 is discharged from the discharge port. The first gas pressure-increasing means 22 is not limited to a reciprocating compressor, and may be, for example, a turbo compressor.

The second path 26 is a path for taking out the first low-temperature liquefied gas L1 from the first tank 21. As shown in fig. 1, one end of the second path 26 is connected to the pump 29 disposed in the first tank 21, and the other end is connected to a point P1 on the first path 23 on the downstream side of the first gas pressure-increasing means 22. Further, the reliquefaction heat exchanger 40, the pump 24, and the vaporizing mechanism 25 are arranged in this order from upstream to downstream in the second path 26. That is, the second path 26 includes: a portion connecting the discharge port of the pump 29 and the inlet of the reliquefaction heat exchanger 40; a portion connecting the outlet of the reliquefaction heat exchanger 40 and the inlet of the pump 24; a portion connecting an outlet of the pump 24 and an inlet of the vaporizing mechanism 25; and a portion connecting the outlet of the vaporizing mechanism 25 and the first path 23 (point P1).

The first low-temperature liquefied gas L1 introduced from the first tank 21 into the second path 26 passes through the reliquefaction heat exchanger 40 and is then drawn into the pump 24. Then, the first low-temperature liquefied gas L1 is pressurized by the pump 24 to a predetermined pressure and then is discharged from the pump outlet toward the vaporizing mechanism 25.

The vaporizing unit 25 is a heat exchanger for vaporizing the first low-temperature liquefied gas L1 pressurized by the pump 24. As shown in fig. 1, the vaporizing mechanism 25 includes: a first flow path 25A through which the first low-temperature liquefied gas L1 discharged from the pump 24 flows; and a second flow path 25B through which a predetermined heat medium (for example, seawater) flows. In the vaporization mechanism 25, the first low-temperature liquefied gas L1 flowing through the first flow passage 25A exchanges heat with the heat medium flowing through the second flow passage 25B (the heat is absorbed from the heat medium by the first low-temperature liquefied gas L1), and the first low-temperature liquefied gas L1 vaporizes to generate the first gas G1. The first gas G1 flows out of the vaporizing mechanism 25 (first flow path 25A), and then merges with the first gas G1 flowing through the first path 23 at a point P1. The vaporizing unit 25 may vaporize the first low-temperature liquefied gas L1, and may be, for example, an open rack LNG vaporizer, a shell-and-tube heat exchanger, or a plate heat exchanger.

The reliquefaction path 28 is a path for liquefying only a part of the first gas G1 extracted from the upstream side of the first gas pressure increasing means 22 in the first path 23 and flowing the liquefied gas into the upstream side of the pump 24 in the second path 26. As shown in fig. 1, the reliquefaction path 28 includes: a main path 28A having one end connected to a point P2 on the upstream side of the first gas pressure-increasing means 22 in the first path 23 and the other end provided with the reliquefaction heat exchanger 40; and a branch path 28B branching from a point P3 in the main path 28A and merging with the main path 28A at a point P4 on the downstream side of the point P3.

A reliquefaction gas pressure increasing means 41 for increasing the pressure of the first gas G1 extracted from the first path 23 is disposed upstream of the point P3 in the main path 28A. The reliquefaction gas pressure increasing means 41 is formed by a reciprocating compressor as in the case of the first gas pressure increasing means 22, but the discharge pressure is smaller than that of the first gas pressure increasing means 22 because the first gas G1 is fed under pressure.

The reliquefaction heat exchanger 40 is, for example, a direct contact heat exchanger, and exchanges heat between the first low-temperature liquefied gas L1 taken out from the first tank 21 through the second path 26 and the first gas G1 flowing in through the reliquefaction path 28 by bringing them into contact with each other. Accordingly, the first gas G1 is cooled and liquefied by the first low-temperature liquefied gas L1. Then, the first cryogenic liquefied gas L1 obtained by this reliquefaction is guided to the pump 24 through the second passage 26 together with the first cryogenic liquefied gas L1 delivered from the first tank 21. The reliquefaction heat exchanger 40 is not limited to the direct contact heat exchanger, as long as at least a part of the first gas G1 is liquefied.

as shown in fig. 1, a cooling heat exchanger 27 for cooling the first gas G1 flowing from the point P3 into the branch passage 28B is disposed in the branch passage 28B. The cooling heat exchanger 27 is an important component of the gas supply system 1 according to the present embodiment, and details thereof will be described later.

As described above, according to the reliquefaction path 28, the first gas G1 (boil-off gas) can be taken out from the upstream side (point P2) of the first gas pressure increasing means 22 in the first path 23, and at least a part of the first gas G1 can be liquefied in the reliquefaction heat exchanger 40. Then, the liquefied first gas G1 (the first low-temperature liquefied gas L1) can be caused to flow into the second path 26 on the upstream side of the pump 24.

Further, not all of the first gas G1 flowing into the reliquefaction heat exchanger 40 through the reliquefaction path 28 is liquefied, and there is also first gas G1 in a gaseous state. Thus, the first gas G1 that has not been liquefied in the reliquefaction heat exchanger 40 is depressurized by the expansion valve 43 and then returned to the first path 23 (upstream of the point P2) through the return path 42.

Next, the structure of the second gas supply unit 1B that supplies the second gas G2 (hydrogen gas) will be described. As shown in fig. 1, the second gas supply section 1B mainly has a second tank 31, a third path 32, and a fourth path 34.

The second tank 31 is for storing a second low-temperature liquefied gas L2 (liquid hydrogen). The second low temperature liquefied gas L2 is stored in the second tank 31 at a temperature of about-252 ℃. In the second tank 31, as in the first tank 21, a part of the second low-temperature liquefied gas L2 is vaporized (evaporated) by heat or the like from the outside, thereby generating a second gas G2 (hydrogen gas).

The third path 32 is a path into which the second gas G2 that occurs within the second tank 31 flows. As shown in fig. 1, one end of the third path 32 is connected to the upper portion of the second tank 31, and the other end is connected to the consumer 100. Further, a second gas pressure-increasing means 33 for increasing the pressure of the second gas G2 to a predetermined pressure is disposed in the middle of the third path 32. The second gas pressure-increasing means 33 is formed by a multistage reciprocating compressor, as in the case of the first gas pressure-increasing means 22. Accordingly, the second gas G2 generated in the second tank 31 is supplied to the second gas pressure-increasing means 33 through the third path 32, and can be increased in pressure to a predetermined pressure by the second gas pressure-increasing means 33.

The other end of the first path 23 of the first gas supply unit 1A is connected to a point P5 on the downstream side of the second gas pressure increasing means 33 in the third path 32. Therefore, at the point P5, a mixed gas G3 is obtained by mixing the first gas G1 and the second gas G2, and the mixed gas G3 is delivered toward the demand side 100.

The fourth path 34 is a path for taking out the second low-temperature liquefied gas L2 stored in the second tank 31. As shown in fig. 1, one end of the fourth path 34 is immersed in the second low-temperature liquefied gas L2 in the second tank 31, and the other end is connected to a point P6 between the second gas pressure-increasing means 33 and the point P5 in the third path 32. Further, a pump 36 and a cooling heat exchanger 27 for conveying the second low-temperature liquefied gas L2 under pressure in the fourth path 34 are disposed in the fourth path 34, respectively.

The cooling heat exchanger 27 is used to cool the first gas G1 flowing through the reliquefaction path 28 (branch path 28B) by heat exchange with the second low-temperature liquefied gas L2 sent from the second tank 31 (using the cold heat of the second low-temperature liquefied gas L2). As shown in fig. 1, the cooling heat exchanger 27 includes: a first channel 27A connected to a branch channel 28B of the reliquefaction channel 28; and a second flow path 27B connected to the fourth path 34. The first gas G1 flowing from the point P3 into the branch passage 28B flows through the first passage 27A, and the second low-temperature liquefied gas L2 supplied from the second tank 31 through the fourth passage 34 flows through the second passage 27B.

Therefore, according to the cooling heat exchanger 27, the first gas G1(LNG boil-off gas) flowing through the first flow path 27A can be cooled by the second low-temperature liquefied gas L2 (liquid hydrogen) flowing through the second flow path 27B. That is, by cooling the first gas G1 using the cold heat of the liquid hydrogen, the liquefaction efficiency of the first gas G1 in the reliquefaction heat exchanger 40 can be improved. Further, according to the cooling heat exchanger 27, the second low-temperature liquefied gas L2 flowing through the second flow path 27B can be warmed by the first gas G1 flowing through the first flow path 27A. The second low-temperature liquefied gas L2 is gasified by heat exchange with the first gas G1 to become the second gas G2, and merges with the second gas G2 flowing through the third path 32 at the point P6.

Here, the features and operational effects of the gas supply system 1 according to embodiment 1 described above are described.